Oak bracket (Inonotus dryadeus)


Common host(s)                    Various Quercus species, commonly found on native oaks

Colonisation strategy            The infection starts in the inner part of the root systems, progresses to the central buttress and may move up the stem for several metres.

Symptoms                              Large, corky brackets, which can appear in groups or solitary. The brackets are cushion-like and yellow when young and exude brownish droplets. The brackets are annual and can be found throughout the year, but they sporulate in late summer to autumn. Irregular fruiting intervals make this fungus hard to detect.

Type of rot                             White rot

Part(s) of tree affected          Stem base, buttress and roots

Significance                            In advanced stages the wood is seriously weakened and wind-throw can occur. Failures due to this fungus are uncommon, but if found on trees in high risk sites, the stem and roots should be investigated

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